diff --git a/backend/app/schemas/audit.py b/backend/app/schemas/audit.py
index e46bac0..e0acb7a 100644
--- a/backend/app/schemas/audit.py
+++ b/backend/app/schemas/audit.py
@@ -2,7 +2,7 @@
 
 import uuid
 from datetime import datetime
-from typing import Any
+from typing import Any, Optional
 
 from pydantic import BaseModel, ConfigDict
 
@@ -16,7 +16,7 @@ class AuditLogOut(BaseModel):
     action: str
     entity_type: str | None = None
     entity_id: str | None = None
-    timestamp: datetime
+    timestamp: Optional[datetime] = None
     details: dict[str, Any] | None = None
 
     model_config = ConfigDict(from_attributes=True)